The FAA announced this week it is ready to go full scale with its implementation of the Automatic Dependent Surveillance-Broadcast (ADS-B) system to track aircraft. The agency expects the transition, which will give air-traffic controllers another tool to track aircraft, to be complete by 2013 and mandated by 2020.

As this development plays out, though, a smart phone application that allows the technology to track aircraft with a phone camera has come under fire from a British security official.

Patrick Mercer, former chair of the UK’s Parliamentary Counter Terrorism subcommittee, according to a Press Trust of India report, said terrorist could use an iPhone application to locate and target an in-flight aircraft for an missile attack.

“Anything that makes it easier for our enemies to find targets is madness,” he reportedly said.

The article also mentions, without specifics, that the Department of Homeland Security also “is investigating how to protect aircraft from attacks.”

This line of thought has its critics as well, however. Marcus Yam, writing for the technology web site TomsGuide.com, commented smarmily: “Next thing he’ll go after are telescopes and binoculars.”

Louisville pilot Robert Patterson said as much this week to us. He hosts an ADS-B receiver on the system used by PlaneFinder.net, which sells the smart phone application.

Louisville International Airport (SDF) was chosen by the FAA as a test site for the system largely due to the UPS fleet that flies cargo into and out of the city daily. Patterson, an aviation enthusiast who does similar hosting for LiveATC.net, said he has enjoyed using the new technology and thinks it should be there for others.

“(It's) Innocent,” he tweeted to us on about the tracking system, after we posted a link to the initial criticism on our Twitter feed.

In a follow-up phone interview, Patterson noted that the tracking data broadcast by the receivers is easy to come across. Anyone can buy and connect one to a laptop via USB for about $700.

“If they can afford an RPG (rocket-propelled grenade), the price of the (ADS-B) antenna probably isn’t going to stop them,” he said.

The only difference between having it on a highly mobile laptop versus a smart phone app, he said, is the price.

Patterson said it would be a disservice to the aviation community to block access to the applications, which cost around $5, as many who would enjoy following flights in their neighborhoods might not opt for the pricier antennas. At least one aviation authority agrees, it seems.

Yam also notes in his report that “the UK Department of Transport doesn’t seem that worried, though, as it said, ‘This application might be new but the ability to track aircraft isn’t.”

How else are we going to have fun with aircraft when we are stuck on the ground?